Turkish officials say the military has been firing at Kurdish rebel positions inside northern Iraq since a rebel ambush near the border Sunday that killed 12 Turkish soldiers.

The officials say Turkish artillery units shelled suspected rebel bases across the border Tuesday night. Turkey's official news agency says warplanes bombed rebel positions along the Turkish-Iraqi border Wednesday.

Officials say the shelling is in retaliation for Sunday's ambush in southeastern Turkey, and not part of any large-scale incursion into Iraq.

Turkish military and political leaders held a meeting of the National Security Council in Ankara Wednesday, to discuss possible further measures against rebels of the Kurdistan Workers' Party, or PKK.

In another development, Iraqi President Jalal Talabani denied Turkish reports that he had offered to extradite rebel leaders to Turkey. He said in a statement today that the PKK leaders live in the mountains of northern Iraq with their fighters, so it is impossible to arrest them and hand them over.

Earlier, Turkish officials said Mr. Talabani told Turkey's Foreign Minister Ali Babacan during talks Tuesday that Baghdad might agree to hand over Kurdish rebels hiding in northern Iraq.

A high-level delegation from Iraq is expected to visit Ankara for talks with Turkish officials Thursday. Babacan says he expects the delegation to come with concrete proposals for ways to defuse tensions along the border.

In Washington, White House spokeswoman Dana Perino warned against the escalation of tensions between Turkey and Iraq. She urged the two sides to exercise restraint, saying both Iraqis and Turks agree the common enemy is the PKK.

The European Union today also urged Ankara to refrain from launching a military incursion into Iraq to counter the rebels.

Turkey has built up its forces along the Iraq border, deploying about 10,000 troops.

The PKK has been fighting for Kurdish autonomy in southeastern Turkey since 1984. More than 30,000 people have died in the conflict.

Some information for this report was provided by AFP and Reuters.